The invention is suitable for use in rotary-type couplers, especially rotary-type F couplers utilized on gondola cars. A pin is used in such couplers to fasten the shank of the coupler head to the yoke of the coupler. The yoke is provided with an opening through which the pin is inserted into coupling engagement with the yoke and shank. It is possible for the pin to fall out under certain conditions. Therefore, it is desirable to cover the opening in the yoke to retain the pin in position.
Most cover plates are normally rigidly bolted over openings, thereby requiring an operator, to carry, among other things, a wrench for removing the nuts from the bolts to free a cover plate for removal from an opening. Many times, the nuts and bolts are rusted together making it virtually impossible to remove the cover plate. Thus a great deal of time can be lost in removing cover plates which are conventionally anchored by nuts and bolts. Moreover, it is not possible to use such an assembly, in this instance, because of the close tolerances between the shank of the coupler, the yoke, and the carsill or housing for the yoke. The invention is directed to the provision of a unique retainer plate which is easily removed for ready access to the opening which it covers. A few simple tools, normally carried by an operator are all that is required to lock and unlock the retainer plate in position on the yoke in blocking relation to the opening.
Briefly stated, the invention is in a rotary type coupler comprising a yoke with a longitudinal axis and a coupler head with an attached shank which is inserted longitudinally within the yoke. Means are provided for mounting the shank of the coupler head within the yoke for rotation about the longitudinal axis of the yoke, such means including a removable pin which holds the shank within the yoke. An opening, disposed in the yoke, is provided so that the pin can be removed from the shank and yoke. A pair of oppositely disposed arcuately shaped grooves are formed in the yoke adjacent the opening and a pair of abutments are disposed adjacent the pair of grooves. A plate for retaining the pin in position with the yoke and shank of the coupler head, is provided and has a pair of oppositely arcuately configured sides which are insertable in the grooves by rotation of the plate in one direction. A stop is carried by the retainer plate for engaging one of the pair of abutments to limit rotation of the cover plate in the one direction. Means, coacting with the cover plate, are provided for engaging the other of the pair of abutments to restrict rotation of the retainer plate in an opposite direction, when the stop engages the abutments, to firmly anchor the retainer plate in position.